TY - JOUR
T1 - Role of <em>rpoS</em> in Stress Survival and Virulence of <em>Vibrio cholerae</em>
JF - Journal of Bacteriology
JO - J. Bacteriol.
SP - 773
LP - 784
VL - 180
IS - 4
AU - Yildiz, Fitnat H.
AU - Schoolnik, Gary K.
Y1 - 1998/02/15
UR - http://jb.asm.org/content/180/4/773.abstract
N2 - Vibrio cholerae is known to persist in aquatic environments under nutrient-limiting conditions. To analyze the possible involvement of the alternative sigma factor encoded byrpoS, which is shown to be important for survival during nutrient deprivation in several other bacterial species, a V. cholerae rpoS homolog was cloned by functional complementation of an Escherichia coli mutant by using a wild-type genomic library. Sequence analysis of the complementing clone revealed an 1.008-bp open reading frame which is predicted to encode a 336-amino-acid protein with 71 to 63% overall identity to other reported rpoS gene products. To determine the functional role of rpoS in V. cholerae, we inactivatedrpoS by homologous recombination. V. choleraestrains lacking rpoS are impaired in the ability to survive diverse environmental stresses, including exposure to hydrogen peroxide, hyperosmolarity, and carbon starvation. These results suggest that rpoS may be required for the persistence of V. cholerae in aquatic habitats. In addition, the rpoSmutation led to reduced production or secretion of hemagglutinin/protease. However, rpoS is not critical for in vivo survival, as determined by an infant mouse intestinal competition assay.
ER -